1. Field of the Invention
The present invention is directed to efficient thermal-mechanical control of thermal energy flow paths in systems which require thermal energy transfer.
2. Description of the Prior Art
Thermoelectric coolers are known for providing efficient, light weight mechanisms to maintain detectors, such as those used for sensing infrared radiation energy in air-to-air missiles, at proper operating temperatures. However, a thermoelectric cooler must be able to dissipate the heat removed from its associated detector in order to maintain its efficiency. It has been proposed that a low resistance thermal path be provided between the hot electrode of the thermoelectric cooler and the skin of the missile. This provides a sufficient temperature gradient when the aircraft carrying the missile is flying at subsonic speeds, since the air flow over the skin of the missile cools the skin. However, when the aircraft travels at supersonic speeds, the skin temperature of the missile may become hotter than the hot electrode of the thermoelectric cooler and cause a reverse temperature gradient that will adversely effect the operation of the thermoelectric cooler and, consequently, the operations of the detector.
An alternative approach is to thermally isolate the interior of the missile from the skin and store the heat, removed by the thermoelectric cooler, in a heat sink within the interior of the missile. Unfortunately, when the aircraft returns to base without firing the missile, the heat stored within the heat sink must be removed before the missile may be flown again. A further disadvantage to an isolated heat sink system is that when the missile is stored in hot climates, it may be necessary to use an auxiliary refrigeration system to cool down the heat sink before each flight.